Sydney wife killer's brutal past revealed

Convicted wife killer Christopher Cullen jumped up and down on a prison guard, smashed someone's upper jaw with a knuckle duster and head-butted a police officer, court documents reveal.

The details of the criminal past of Cullen, who murdered his estranged wife with two fishing knives after concluding she was having an affair, came out in documents during a sentencing hearing in Sydney on Thursday.

Victoria Comrie Cullen's battered body was found by a passer-by at Taren Point fishing club, in the city's south, on January 22 last year.

The 39-year-old had a broken nose, bruised eyes and 18 sharp force injuries, including two neck wounds that had cut down to her vertebrae.

Cullen was found guilty of her murder earlier this month after a jury rejected the 51-year-old's claim that he was provoked and acted in excessive self-defence when he carried out the killing.

What the jury did not know was Cullen's violent criminal past.

Court papers reveal that when he was 20 and still living in the UK, he was convicted of assault for punching the manager of a public house in the face after he was asked to leave.

In 1986, when he was 22, he was convicted of another assault, this time after he kicked someone in the face.

Then, while on remand at Wormwood Scrubs Prison in London in the same year, he began an argument with a prison officer.

"This resulted in him punching and kicking and jumping up and down on the prison officer," the court papers said.

Cullen was again convicted of assault and given a suspended sentence.

A year later in 1987, he was at a building site in Ilford, north-east of London, when an argument broke out between him and his employer who owed him money.

Cullen then headbutted and punched him, fracturing the employer's cheekbone and nose.

Court papers also said Cullen headbutted and punched a police officer while being held in a detention room.

Finally in 1994, he was sentenced to two years in prison after being convicted of grievous bodily harm in Essex.

Court papers said Cullen struck "the victim in the face with a knuckle duster".

"The victim sustained a smashed upper jaw and will need surgery to rectify this."

Cullen is set to be sentenced over his wife's murder next month.